In order to obtain current capacity as a connecting means between an FET (Field Effect Transistor) and a microwave transmission line, the ingenuity which approaches to place a plurality of same-shaped bonding wires in parallel is given. Moreover, also in order to make inductance small as a connecting means between the FET and the microwave transmission line, the ingenuity which approaches to place a plurality of same-shaped wires in parallel is given.
The semiconductor device used with a high frequency band, for example, a microwave power amplifier, is composed of active elements, such as FETs, passive elements, such as resistance, a capacitor, and circuit elements, such as a microstrip transmission line for transmitting a high frequency signal. In such a microwave power amplifier, as shown in FIG. 1, for example, the FET is formed on a semi-insulating substrate 100, and includes a gate terminal electrode G, a source terminal electrode S, and a drain terminal electrode D which are disposed on a first surface of the semi-insulating substrate 100. The gate terminal electrode G is connected to an input circuit pattern on a dielectric substrate 26 disposed at an edge part by an input bonding wire 12. Similarly, the drain terminal electrode D is connected to an output circuit pattern on a dielectric substrate 28 disposed at an edge part by an output bonding wire 14, for example.
In the example of FIG. 1, in the source terminal electrode S, a VIA hole SC is formed from the backside of the semi-insulating substrate 100, and a ground conductor 125 is formed on the backside of the semi-insulating substrate 100. And when grounding a circuit element, the circuit element provided on the semi-insulating substrate 100 and the ground conductor 125 formed on the backside of the semi-insulating substrate 100 are electrically connected via the VIA hole SC which passes through the semi-insulating substrate 100.
About a microwave amplifier which modulates the inductance of the bonding wire of the edge part by adjusting the length of the bonding wire of the edge part, it is already disclosed (for example, refer to Patent Literature 1).